Electric-arc lamp



J. A. HEANY.

ELECTRIC ARC LAMP.

APPLICATION FILED IUNE n. 1911.

Patented Jan. 10, 1922.

by declare the followin PATENT OFFICE.

JOHN ALLEN HEANY,

OF NEW YORK, N. Y.

ELECTRIC-ABC LAMP.

1,403,079. Specification of Application filed June 11,

To all whom it may concern:

Be it known that 1, JOHN ALLEN HEANY, a citizen of the United States,residing in the city, county, and State of New York, have inventedcertain new and useful Improvements in Electric-Arc Lamps; and I dohereto be a full, clear, and exact description 0 the invention, such aswill enable others skilled in the art to which it appertains to make anduse the same.

The invention relates to electric arc lamps operating on very lowwattages and at the ordinary commercial voltages and maintaining highefiiciencies even in the smaller sizes ranging as low as ten or fifteencandle power. To this end, the invention comprises a lamp, involving acontainer or envelope, preferably adapted for connection in the ordinaryincandescent lam socket and containing an inert gas, prefera 1y underdiminished pressure, and two electrodes, between which the arc isestablished and maintained, connected to suitable lead wires, at leastone of which electrodes comprises a body portion of highly refractoryoxide which is a nonconductor of electricity, but which incandesces at ahigh temperature, and having a terminal made of an admixture ofrefractory oxide and refractory metal, the body ortion of said electrodebeing surrounded y a coil of highl refractory metallic wire, which isconnecte to the terminal aforesaid, to serve as a ballast resistance, aluminant body per se, and a heating element, the coacting electrode beinnormally in contact with the terminal of t e other electrode andpreferably mounted u on a thermostat which operates to separate t eelectrodes to proper arcing distance, when the current passes throughthe lamp.

In the accompanying drawing, the figure illustrates a lamp embodying thepreferred form of the invention.

Referring to the drawing, 1 indicates the globe or bulb of the lamp,which is preferably in the form usually employed in incandescentfilament lamps, adapted for the usual socket connection, which bulb isexhausted of air and supplied with an inert gas, such as nitrogen,argon, or the like, preferably under diminished pressure. The bulb isprovided with the usual form of glass neck 2, carrying the usual leadwires connected to the lamp terminals, to one of which lead wires isattached by means of :1

Le te Paten Patented Jan. 10, 1922.

1917. Serial No. 174,103.

lead 3, a wire coil 4 made of highly refractory metal such as tungsten,which coil surrounds and supports a rod-like element 5 of highlyrefractory non-conductive material, such as thorium oxide, to the end ofwhich is secured a terminal 6 formed of an intimate admixture of highlyrefractory oxide w or oxides and finely divided and preferably highlyrefractor metal, such as tungsten, dispersed throug out the same torender said terminal conductive. formed by mixing the refractorymaterial of which it is made with a dissipating'binder, moulding theplastic mass into the desired form and then sintering the same to driveoff the binder and harden the rod. The terminal 6 is formed in the sameway and is provided with a depression having a diameter slightly largerthan the diameter of the electrode. The terminal is placed on theelectrode so that the end of the electrode extends into the depression,after which the terminal is fused to the electrode. The end of the coil5 is fused to said terminal 6.

The coacting electrode may, if desired, be formed substantially likethat described, but preferably consists of a ball-like element 7 ofhighly refractory metal, such as tungsten orv tungsten alloy, or acomposition of the same eneral character as terminal 6 of the oppositeelectrode. Said electrode 7 is secured to the lower end of thethermostat 8, which in turn is connected to the opposite lead wire ofthe lamp. The thermostat is adjusted to hold the arcing ends of theelectrodes normally in contact and to separate the electrodes to properarcing distance when the lamp is operating.

When current is turned into the lamp, it enters by way of lead 3, passesthrough the ballast and heating coil 4, thence to terminal 6, toelectrode 7 in contact therewith, through the thermostat 8, back to theother terminal of the lamp. The effect of the passage of the current isto highly heat the wire coil 4, raise the same to incandescence, and atthe same time to raise the temperature of the refractory oxide rod 5 tothe point where said rod becomes incandescent. The heat developed actingupon thermostat 8 causes the same to move electrode 7 away from theterminal (3 of the opposite electrode and establish an arc between saidterminals. When the arc is established, it is maintained with a steadybrilliancy and quality approximating thatof sunlight, and is augmentedby the The electrode 5 is.

incandescence of the refractory wire coil 4 and the rod-like bodyportion 5 of refractory oxide.

What I claim is z- 1. An arc lamp comprising a container, havingsuitable circuit connections, an electrode attached to one of saidconnections including a body portion formed of highly refractory oxidelaving a terminal of a mixture of refractory oxide and refractory metaland a heating and ballast coil of refractory metal surrounding saidiefractory material and connected to the terminal, a second electrodenormally in contact with the terminal of the first electrode, and meansfor moving said electrodes apart to establish an arc therebetweeni- 2.An arc lamp comprising a container, having suitable circuit connections,an electrode attached to one of said connections including a bodyportion formed of highly refractory oxide having a terminal of a mixtureof refractory oxide and refractory metal and a heating and ballast coilof refractory metal surrounding said refractory material and connectedto the terminal, a second elecan electrode in said container formed of amixture of a highly-refractory oxide and refractory metal, a secondelectrode normally in contact with said first electrode circuitconnections for said electrodes including a ballast coil of refractorymetal enveloping a core of refractory oxide, and means for moving saidelectrodes apart to establish an arc therebetween.

4. An arc lamp comprising a container, an electrode in said containerformed of a mixture e-i'ii-g'rlflyaremetery oxide and re fractory metal,a second electrode normally in contact with said first electrode,circuit connections for said electrodes including a ballast coil ofrefractory metal enveloping a core of refractor oxide, a thermostatadapted to move sai electrodes apart to establish an are.

In testimony whereof I aflix m si nature.

JOHN ALLEN E NY.

